January 14, 2012

Phobos-Grunt Expected To Return To Earth This Weekend

by editor

The Russian probe that has been stranded in Earth's orbit since its November launch is expected to return to Earth within the next few days, according to various media reports Friday.

Brian Vastag of the Washington Post said that the Phobos-Grunt spacecraft, which was to travel to Mars to study one of that planet's two moons, "will plunge to its doom this weekend, likely on Sunday." Ned Potter of ABC News wrote that the probe would "most likely" fall back to Earth on Sunday or Monday.

Most of the 13.5-ton spacecraft is expected to be incinerated in the atmosphere, but according to Potter and Vastag, officials with Roscosmos (the Russian federal space agency) believe that between 20 to 30 pieces of debris weighing a combined 450 to 500 pounds could reach the planet's surface.

The location where the debris will land is currently unknown, as may not be known for sure until just a few hours before the actual touchdown, according to ABC News. The Washington Post says that it could "plummet back to Earth over North America, South America, Europe, Asia, or even Australia."

"The agency´s latest prediction shows it crashing into the Atlantic Ocean just off the coast of South America," Vastag said. "But that prediction can – and most likely, will – change“¦ As the craft drops lower and lower, its path will grow more certain."

By late Saturday evening, the European Space Agency (ESA) will be able to eliminate possible landing points, officials told the Post. Vastag reports that the ESA currently predicts that the re-entry will occur on Sunday morning, Eastern time, but could happen as early as Saturday night or possibly as late as sometime Monday morning.

Potter reports that there is just a 1 in 20 trillion chance that any individual person could be hit with debris, based on the vehicle's orbit and the amount of debris expected to survive re-entry.

Vastag added that scientists predict that the 11 tons of toxic fuel on board Phobos-Grunt will likely "explode high in the atmosphere as friction eats through the craft´s aluminum tanks," preventing a potential environmental disaster.

Earlier this week, Roscosmos chief Vladimir Popovkin told reporters that the failure of the Phobos-Grunt launch and other Russian satellite failures over the past year may have been the result of sabotage by foreign countries, perhaps even the United States.

"I wouldn´t like to accuse anyone, but today there exists powerful means to influence spacecraft, and their use can´t be excluded," Popovkin said in an interview with Izvestia daily, adding that it was not clear why several launches experienced problems at the precise instant that they began travelling through areas invisible to Russian radar.

"It is unclear why our setbacks often occur when the vessels are travelling through what for Russia is the ℠dark´ side of the Earth – in areas where we do not see the craft and do not receive its telemetry readings," he continued, acknowledging that the Phobos-Grunt mission was also risky because it involved a project that was underfunded and whose design dated back several years.

"If we did not manage to launch it in the window open in 2011 for a Mars mission, we would have had to simply throw it away, writing off a loss of five billion rubles ($160 million)," Popovkin, who took over as the head of Roscosmos in April, also said.

The $165-million Phobos-Grunt probe was expected to embark on an eight-month journey to one of the two moons of Mars, where it have would retrieve a soil sample that would be returned to Earth for analysis. It was the latest in the long line of Russian satellite failures, and the nation also experienced the failure of a Progress cargo ship headed for the International Space Station (ISS).

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Image Caption: The flight version of the Phobos-Grunt spacecraft minus its main solar panels is being lowered into a vacuum chamber at NITs RKP test facility in Peresvet, north of Moscow, for thermal, vacuum and electric tests around beginning of June 2011. Credit: NPO Lavochkin